This project proposes to evaluat e the role of lymphokines in the intestinal mucosal cell-mediated immune respone of patients affected by inflammatary bowel disease. An inflammatory process is generally the resule of cell-mediated immune phenomena. The extent and duration of the inflammatory reaction are regulated by soluble factors released by some immnocopetent cells, such as T lymphocytes and macrophages. Such soluble factors, or lymphokines, have been shown to play a fundamental role in the behavior of various types of cells involbed in mitogen or antigen stimulated immune response. Similar events must occur at the intestinal level in patients affected by ulcerative colitis and Crohn's diseas. The mononuclear cells responsible for the gut inflammatory reaction can now be isolated in large numbers and with intact functional capilities. We have found that many of the recovered gut mucosal lymphoid cells re in an activated state and, therefore, likely to be conditioned to release mediators of cellular immunity. Using such cells, we propose to evaluate the production of the following lymphokines: (1) leukocyte derived chemotactic factor, (2) leukocyte migration inhibitoar factor, (3) T cell growth factor, (4) interferon and (5) prostaglandins. We feel that the evaluation of these lymphokines can contribute to the further understanding of mechanisms responsible for tissue damage and cronicity in inflammatory bowel disease